RF 433MHz Transmitter/Receiver range

[makaveledj]

Hello I have KC868 A16v3 board together with the RF 433MHz Receiver/Transmitter which comes in the pack. 

I have very short range about 6m straight line with no obstacles. Is it the Transmitter/Receiver that limits the range? 
How can I improve it to have better range? 
Should I buy transmitter/receiver with antenna, and if so, could you recommend me which model is compatible with the board?

Thank you

[admin]

sorry, i don't know your RFID Receiver/Transmitter. what you have connect with each other? by cable? take a photo is better.

[makaveledj]

I apologize for the mistake, I meant the RF 433MHz modules receiver/transmitter which comes with the board. They have very limited range maximum 6 meters. How can I improve it?

[admin]

you can solder a antenna to RF module. on RF sender/receiver module , there is a pcb hold for solder antenna. you can solder a exend wire is ok.